Conventional microscopes, e.g. surgical microscopes, comprise a permanently incorporated illumination system with which a specimen or object to be viewed is illuminated. The illumination system can be embodied as a reflected-light and/or transmitted-light system.
Highly sensitive specimens exist, however, that can be damaged by visible light, UV light, or even IR light. An example that may be given here is the human eye that is being viewed by means of a microscope in the context of an ophthalmic operation.
The present invention strives to make available a microscope, in particular a surgical microscope, in which damage to the specimen being observed as a result of the light used for illumination of the specimen is minimized or entirely avoided.
A microscope having the features of claim 1 is proposed for this purpose.
With a microscope according to the present invention, the light intensity necessary for observation or for sufficient illumination of a specimen can be significantly reduced as compared with conventional solutions. Night vision apparatuses usable according to the present invention are available relatively economically. The solution according to the present invention makes a significant contribution toward reducing stress on light-sensitive specimens that are being examined under a microscope. The solution according to the present invention is moreover physically small and compact, so that it is readily usable for numerous applications. In particular, night vision device can advantageously be integrated into the microscope housing.
A night vision apparatus can be introduced into the normal beam path of a microscope, i.e. for example positioned on an optical axis defined by a main objective and/or a zoom system. It is likewise possible to couple out additional beam paths for a night vision apparatus. A beam path coupled out in this fashion can be delivered to a suitably positioned night vision apparatus. An image generated by means of the night vision apparatus can then be displayed on a monitor. It is likewise conceivable to superimpose the image generated by the night vision apparatus back onto the normal beam path of the microscope. Depending on the superimposition location, a magnification generated in the normal beam path must be compensated for in the image provided by the night vision apparatus.
The microscope is embodied in particular as a stereomicroscope. The invention proves advantageous in particular in connection with the stereoscopic viewing of a specimen, since good stereoscopic observation is possible here even with very dim or weak light.
Advantageous embodiments of the microscope according to the present invention are the subject matter of the dependent claims.
Stereomicroscopes of this kind are usable in particularly advantageous fashion as surgical microscopes.
In this connection, reference may be made to the following: In principle, any number of night vision apparatuses can be provided for a microscope according to the present invention. For example, two night vision devices can be provided for a stereomicroscope. These night vision apparatuses can be introduced into the respective stereoscopic observation channels, or can be impinged upon by further beam paths proceeding from a specimen to be observed.
It is likewise possible to provide only a single night vision apparatus for a number of beam paths, for example for both normal observation beam paths of a stereomicroscope, and to obtain images sequentially, for example by means of a suitable time-related control system, for the respective beam paths or observation channels. Images acquired shortly after one another (sequentially) can be viewed stereoscopically, without substantial degradation or perceptible time delay for an observer, by being presented, for example, on an autostereoscopic display or on a display having polarization display means.
According to a preferred embodiment of the invention, the night vision apparatus is placed downstream and/or upstream from a zoom system of the microscope. An upstream positioning, i.e. for example between the main objective and zoom system of a microscope, proves particularly advantageous, since no attenuation of the limited spectral range that is typically essential for a night vision apparatus occurs as a result of the optical properties of the zoom system (absorption or light attenuation). A superimposition of the image generated by the night vision apparatus with the normal observation beam paths of the microscope can likewise occur before and/or after the zoom system.
A superimposition of the image generated with the night vision apparatus onto the normal beam path or paths of the microscope is, as mentioned, advantageous. Usefully provided for this purpose is a superimposition device with which an image generated by a night vision apparatus can be superimposed onto a normal beam path of the microscope. With such a superimposition, a high-contrast image can be generated in particular in dim light conditions. It is possible in this connection, for example, to electronically process images generated by the one or more night vision devices. Edge emphasis or intensification, as well as color modification or color coding, may be mentioned here by way of example. The term “normal” beam paths refers here to beam paths that do not impinge on the night vision device, but instead pass through the usual components of a microscope, namely e.g. the main objective, zoom system, eyepiece, etc.
Usefully, a superimposition device of this kind comprises means for magnifying or enlarging an image generated by the night vision apparatus. With such means it is possible to introduce the image generated by the night vision apparatus back into the normal beam path even after a magnification system, for example the zoom system.
According to a preferred embodiment of the microscope according to the present invention, generation of a respective image by way of respective night vision apparatuses occurs for two observation channels of a stereomicroscope, the generated images being inputted into a connected computer or one integrated into the microscope and presented stereoscopically on a screen. This feature permits additional or alternative viewing, on the screen, of a specimen to be observed.
It proves advantageous to provide at least one shutter that is extendable into and retractable from the beam paths. With such shutters, a user of the microscope can, for example, select or switch back and forth between a direct observation of the image through the observation channel or channels of the microscope and an image generated by a night vision apparatus, presented on a monitor, and reflected into the observation channel or channels of the microscope. A superimposed observation of these two aforesaid images can also be implemented with appropriate positioning of the shutters or shutter elements.
According to a further preferred embodiment of the microscope according to the present invention, an illumination device can be selectably switched in. An illumination device of this kind can, for example, be switched in for the observation of non-sensitive specimens. An illumination device of this kind can also be quickly switched on, for example, in an emergency. When an illumination device is switched on, an automatic switching off of the respectively provided night vision apparatuses is also conceivable.
According to a further preferred embodiment of the microscope according to the present invention, deflection elements having a variable reflectivity or transmissivity, which can be impinged upon by the respective beam paths, are provided. The concept of “variability” is also intended to encompass the possibility of displacing a beam splitter entirely out of a beam path. This would thus mean a decrease in reflectivity to zero. Stepless variability is also, however, intended to be encompassed in the same fashion. Stepless variability is achievable, for example, by means of micromirror arrays that are usable selectably as fully reflective mirrors, partially transparent, or semitransparent mirrors (beam splitters), or even as entirely transmissive elements.
The invention and its advantages will be further explained below with reference to exemplifying embodiments that are illustrated in the appended drawings. It is understood that the features of the invention discussed and yet to be discussed are usable not only in the respective combination indicated, but also in other combinations or in isolation, without departing from the context of the present invention. Different embodiments are also, in particular, partially or completely combinable.